I reckon it will depend on what you are trying to do, but get into the equivalent of VBA's Tools | References window and start selecting everything that looks useful...
Things like
PISDK Type Library
PI-SDK Dialogs
PISDKCommon Type Library
PISDK Parse Type Library
PISDKRegistry Type Library
PITimeDLL Type Library
PITimeServer Type Library
PIDataAccess Type Library
PI Data Object Type Library
PI OLEDB Type Library
PI OLEDB Controls
plus (depending on whether you have other OSI products that we don't) or minus (if we have some you don't or what you're trying to do doesn't need them) should get you started...